My cats LOVE this tree! 
Very sturdy- my big 15 lb cat fits in the nest and the top post just fine and it even supports both of my cats in the nest. The kitten plays with the dangle rope and fuzzy ball constantly. I sprinkled a little cat nip at the very bottom and they both use the scratcher. 
This is their favorite spot in the house now, and they are both indooroutdoor and find plenty of stimulation and comfort with this product. Highly recommend.